local WH_URL = "https://discord.com/api/webhooks/id/token"
local IGNORE = { "player1", "player2" }
local DIMENSION = "minecraft:overworld"
local AREA = {
  [0] = { x = 100, y = 0, z = 200 },
  [1] = { x = 200, y = 200, z = 300 }
}
local REDSTONE_SIDE = "front"
local MODEM_PORT = 12345
local modem = peripheral.wrap("back")
local sensor = peripheral.find("playerDetector")
local chatbox = peripheral.find("chatBox")
local KNOWN_PLAYERS = {}
local COOLDOWNS = {}
local COOLDOWN = 0.1

function sendWhMessage(msg)
  local payload = { content = msg } 
  http.post(WH_URL,
            textutils.serializeJSON(payload),
            { ["Content-Type"] = "application/json" })
end

function modemMessage(msg)
  modem.transmit(MODEM_PORT, MODEM_PORT + 1, msg)
end

function findPlayers()
  local players = sensor.getPlayersInCoords(AREA[0], AREA[1])
  return players
end

function getPlayerPos(player)
  local pos = sensor.getPlayerPos(player)
  return pos
end

function isInArr(arr, val)
  for k,v in pairs(arr) do
    if v == val then return k end
  end
  return false
end

function timestamp()
  return (os.day() * 24) + os.time()
end

function isCooldown(player)
  local item = COOLDOWNS[player]
  local time = timestamp()
  return not (not item or item < time)
end

function setCooldown(player)
  COOLDOWNS[player] = timestamp() + COOLDOWN
end

function isIgnore(player)
  return isInArr(IGNORE, player) ~= false
end

function randomRound(num)
  return num + math.random(-5, 5)
end

while true do
  local found = findPlayers()

  -- check for new players
  for k,v in pairs(found) do
    local pos = getPlayerPos(v)
    local inArr = isInArr(KNOWN_PLAYERS, v)

    if pos ~= nil and pos.dimension == DIMENSION and not inArr and not isCooldown(v) and not isIgnore(v) then
      setCooldown(v)
      print("Player "..v.." entered area")
      
      sendWhMessage("Player `"..v.."` entered area "..
        "at `"..pos.x..","..pos.y..","..pos.z.."`.")
    
      table.insert(KNOWN_PLAYERS, v)
      
      chatbox.sendMessageToPlayer("You have entered a restricted area. Leave now if you value your balls.", v, "FSF")
      
      modemMessage(v.." entered at "..randomRound(pos.x)
        ..","..randomRound(pos.y)..","..
        randomRound(pos.z))
    end
  end
  
  -- check if players left the area
  for k,v in pairs(KNOWN_PLAYERS) do
    local pos = getPlayerPos(v)
    if pos ~= nil and (not isInArr(found, v) or pos.dimension ~= DIMENSION) and not isCooldown(v) and not isIgnore(v) then
      setCooldown(v)
      print("Player "..v.." left area")
      sendWhMessage("Player `"..v.."` left area at `"..
        pos.x..","..pos.y..","..pos.z.."`.")
      table.remove(KNOWN_PLAYERS, isInArr(KNOWN_PLAYERS, v))
      
      modemMessage(v.." left at "..randomRound(pos.x)
        ..","..randomRound(pos.y)..","
        ..randomRound(pos.z))
    end
  end
end